As fall turns to winter, Mainers are reminded just how precious sunlight is. Whereas in July, we could linger in the sun’s rays until after 8 p.m., in December it’s dark out before we leave work each day.

In a color-coded, interactive map currently being discussed on the chat board site Reddit, the average daily sunlight of each county in the U.S. is displayed.

The data is attributed to the U.S. Centers for Disease Control and Prevention, and uses units of kilojoules of energy per square meter, as briefly explained in the caption of the map shown above.

In a general sense, the map shows just what you’d expect it to show — that the farther south you get, the greater amount of daily sunlight you get.

While no place in Maine compares to the southern tip of Florida in this regard, Maine’s southernmost county — York County — gets the most sunlight of any place in the state.

York County is the only county in Maine with an average daily sunlight of more than 15,000 kilojoules per square meter.

The county that gets the least sunlight every day is the northernmost county, Aroostook County, which sees significantly less at 13,343.8 kilojoules per square meter.

Why does the amount of sunlight you get matter?

Well, there are the obvious benefits of sunlight on plants, but Mainers are pretty smart about which vegetables and flowers to plant when in order to maximize sun exposure and success rates at this point.

But sun also plays a role in human health as well.

Too much sun can burn your skin, of course, and depending on some other factors, can lead to skin cancer.

Still, sun provides a multitude of benefits when absorbed in reasonable doses.

“The same DNA-damaging, sunburn-causing UVB wavelengths that sunscreens are designed to block also do some good: They kick off the chemical and metabolic chain reaction that produces vitamin D. Research shows that many people have low vitamin D levels. There is a well-documented relationship between low vitamin D levels and poor bone health. Now links have been made to everything from multiple sclerosis to prostate cancer. ‘Linking’ low vitamin D with these diseases doesn’t prove cause-and-effect, but it suggests that possibility. Getting some sun may also shake off the wintertime blues: Research suggests that light hitting your skin, not just your eyes, helps reverse seasonal affective disorder (SAD). Moreover, being outside gets us golfing, gardening, and engaging in other types of physical activity.”

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ThinkMaine is a place for stories, photos and videos that may make you stop and think differently about Maine — about the ecology, history and lifestyles of Maine. Visit this site for thought-provoking information about Maine's science or heritage that puts the state's current and future challenges in perspective.